Housed draft gear



May 30, 1961 c. LUSINK HousED DRAFT GEAR Filed July 20, 1959 In ve ntor: Clarence I. Lusink his Aitorney United States Patent O HOUSED DRAFT GEAR Clarence I. Lusink, Buffalo, N.Y., assignor to Symington Wayne Corporation, Salisbury, Md., a corporation of Maryland Filed July 20, 1959, Ser. No. 828,249

'3 Claims. (Cl. 213-30) 'I'his invention relates to railway draft gears and has for its primary object the provision of a housed draft gear which is an improvement over the cushioning mechanism disclosed in Emil H. Blattner Patent No. 2,540,041, issued January 30, 1951.

Another object of the invention is to provide an improved draft gear of the housed type wherein the housing is strengthened against failure without requiring change in either the over-all dimensions or the capacity of the gear.

An additional object of the invention is to provide an improved draft gear of the housed type using for cushioning` friction and spring units contained iu a housing, wherein the housing, friction unit and plunger are of such arrangement and construction as to inhibit failure of the housing in service without reducing the capacity of the spring unit or that of the draft gear as a whole.

Other objects and advantages of the invention will appear hereinafter in the detailed description, be particularly pointed out in the appended claims and be illustrated in the accompanying drawings in which:

Figure 1 is a view taken along the lines 1-1 of Figure 2 of a preferred embodiment of the draft gear of the present invention;

Figure 2 is a front elevational view of the draft gear of Figure l;

Figure 3 is a vertical sectional view taken along the lines 3-3 of Figure 1;

Figure 4 is a yfragmentary horizontal sectional View of the housing of the preceding figures taken along the lines 4-4 of Figure 3; and

Figure 5 is a fragmentary horizontal sectional view of the housing taken along the lines 5-5 of Figure 4.

Referring now in detail to the drawings, in which like reference characters designate like parts, the improved draft gear of the present invention is designed for the usual installation Within a yoke in a draft gear pocket in the center sills of a railway vehicle between fixed front and rear stop lugs for cushioning bufling and draft forces transmitted to the gear through a coupler.

Of the housed type, the improved draft gear has a housingl 1 having longitudinally extending vertically spaced top and bottom walls 2 connected at the sides by correspondingly extending, horizontally spaced side walls 3. The longitudinal walls 2 and 3 are connected at the rear by a vertically directed rear wall 4 and, together with the rear wall, define a cavity or hollow interior 5 opening through a mouth 6 onto the front end 7 of the housing. Arranged in tandem in the housing 1 and opening onto each other are front or friction and rear or spring pockets or compartments 8 and 9, respectively, the latter of which seats or contains a spring unit 10, preferably in the form of a multiple coil release spring. Bearing at the rear against the rear wall 4, the coil spring 10 bears at the front against an intermediate or oating follower 11, the front face 12 of which bears and is rubbed against by the preferably llat rear ends 13 of a pair of counterpart friction shoes or wedges 14 ICC which, with suitable yieldable or spring means urging them apart, such as the illustrated pair of proposed packs of leaf springs 15, form a friction unit.

For frictional engagement by the friction shoes 14, there are formed on one of the pair of transversely or laterally spaced longitudinal walls 2 or 3 of the housing, opposed, inclined or sloping, forwardly flaring friction surfaces 16, each of which preferably is substantially at and, transversely, is disposed substantially normal to the other pair of Walls. The illustrated gear being designed particularly for use with a vertical yoke (not shown) with the housing thus of greater Width than depth, the iirst or friction surface pair of walls preferably are the side walls 3 and the second pair, the top and bottom walls 2. While each side wall 3 may have a single such friction surface substantially of the length or coterminous with the front or friction pocket 8, it is preferred that it have a pair of substantially parallel friction surfaces arranged in tandem and connected by an instand* ing abutment or shoulder 17. Each of the friction shoes 14 in turn has one or preferably a pair of friction faces 18, preferably flat and inclined or sloping in correspondence and urged into bearing engagement with a confronting friction surface 16 on the adjoining side wall 3' by the yieldable means 15, the preferred pair of friction surfaces on each shoe being connected by an outstanding abut-ment or shoulder 19 which, by engagement with the confronting abutment 17 at that side of the housing, limits the forward movement of the shoes under forcev of the return spring 1t).

While the friction shoes 14 themselves may project forwardly of the housing 1, in the illustrated gear they are contained within the housing 1 in the friction pocket 8, and their preferably flat front ends 25am adapted to rub against a preferably flat rear end 21 of a plunger 22 extending or projecting into the mouth 6 of the cavity 5 and normally -extending forwardly of the housingfor engagement in the installed position of the gear, with a front follower indicated at 23. The illustrated plunger 22 is held in assembled relation in the housing 1 by suitable interlocking means, conveniently in the form ofk a pair of lugs 24, each centered on and integralV with one of the side walls 3 and instanding therefrom into the mouth 6, each of the lugs laterally overlapping but normally being spaced forwardly of one of a pairY of stop means carried by thevplunger, one an integral shoulder 25 and the other a retainer plate 26 removably Y xed, as by welding, to the plunger.

In common wtih the coupling mechanism of Blattner Patent No. 2,540,041, the draft gear of this inventionV is dependent for cushioning buing and draft forces transmitted to it by the associated coupler mainly on the friction engendered by the friction shoes 14 as they move longitudinally relative to the housing 1. The high internal stresses on the housing because of the pressure developed by the shoes 14 and their spring packs 1,5, coupled, in the case of the cushioning mechanism of the patent, with wear by engagement of the shoes and the plunger with the relatively thin walls of the housing at their sides, has tended to develop cracks in the front Y portion of the housing of the mechanism at the corners where the longitudinal walls join. This tendency is eliminated in the draft gear of this invention without reducing theV capacity either of the release spring 10 or of the draft gear as a whole.

In accordance with this invention, the pair of opposite Y longitudinal Walls at the sides of the shoes 14 and the plunger 22, here the top and bottom walls 2, arethicki enedtoward their junctions or connections with the side` walls 3 from the front end 7 of the housing 1, rearwardly, at least to the instanding abutments 17 and preff erably over the front portion 27 of the housing to the rear extremity of the friction pocket 8. This thickening is limited to the side portions 28 of the top and bottom Walls 2 and over their midor central portions 29, these walls are of minimum thickness or unthickened with the confronting inner surfaces or faces 30 of these portions substantially parallel and at maximum spacing to pass, on assembly and disassembly, a release spring comparable in diameter and capacity with that of the cushioning mechanism of the Blattner patent. The side portions 28 themselves are thickened, not uniformly but progressively, outwardly from the midportions 29 and inwardly from the substantially planar and parallel outer faces 31 of the top and bottom walls 2 so that, at either side of the midportions, the confronting side portions converge toward the corners 32 at which the top and bottom walls join or connect with the side walls 3.

Preferably, the shoes 14 would ride on the friction surfaces 16 out of contact with the top and bottom walls 2 and to this end, the shoes are made of such width that their side faces 33 normally are spaced from the inner surfaces or faces 34 of the outer or side portions 28. However, in service, frequent shifting of the shoes vertically or laterally against the top and bottom walls is unavoidable and it is the attendant wear that, in the cushioning mechanism of the Blattner patent, has contributed to the corner cracking. Wear from this cause is reduced to a minimum in the draft gear of this invention by making the side faces 33 of the shoes and the inner surfaces 34 of the side portions substantially flat and laterally inclining or sloping the side faces 33 of each shoe relative to its friction face or faces 18 in correspondence with the lateral inclination, slope or Obliquity of the associated inner surfaces 34 relative to the adjoining friction surface or surfaces 16. As a consequence of the atness and parallelism of the related side faces 33 and inner or bearing surfaces 34, any contact between either shoe and either of the top and bottom walls 2 will be over an extended area. Moreover, since the inclination of the side faces 33 and bearing surfaces 34 is inward relative to the direction of action of the spring packs by which the shoes are urged apart, the bearing surfaces, under the force of the spring packs, will exert a wedging action tending to force the shoes against the friction surfaces 16 on the side walls 3 and away from the top and bottom walls 2 and in any event prevent the shoes from gouging into the corners 32 of the housing.

As mentioned earlier, the tendency of the housing of the cushioning mechanism of the Blattner patent to crack at the corners stems from the wear on its relatively thin side walls by the plunger, as well as the shoes. To eliminate wear from such cause, it therefore is necessary not only that the thickening of the top and bottom walls 2 extend to the front end 7 of the housing 1, but that the outward tapering of the side faces 33 of each shoe 14 and the normal spacing and parallelism between each and the confronting bearing surface 34 on the housing be duplicated in the sides 35 of the plunger at either side of its parallel-sided midportion 36 and that the plunger as a whole conform in lateral or peripheral contour substantially to that of the mouth 6.

The thickening of the top and bottom walls 2 in accordance with this invention thus not only provides maximum thickness in the corners 32 of the housing 1 with a minimum of added metal, but minimizes any Wear to which the top and bottom walls may be subjected and by being limited to the side portions 28 of those walls, eliminates the necessity for any reduction in the capacity of the return spring 1t). Not only is the capacity of the return spring not reduced, but the reduction in the width of the friction surfaces and faces 16 and 18 required to accommodate the thickening at the corners 32 without change in the over-all dimensions of the housing is too slight to produce any appreciable reduction in the forceabsorptive capacity of the friction unit, so that the capacity of the gear as a whole remains unchanged.

It should be understood that the described and disclosed embodiment is merely exemplary of the invention and that all modifications are intended to be included which do not depart from either the spirit of the invention or the scope of the appended claims.

Having described my invention, I claim:

l. In a draft gear having a housing, a friction pocket in and opening onto an end of said housing, a pair of counterpart friction shoes in said pocket and each having a friction face engageable with a friction surface on one of a pair of opposite longitudinal walls of said housing, and yieldable means acting between said shoes and urging said friction faces and surfaces into engagement, the combination of a pair of transversely spaced longitudinal walls connecting said first pair of walls and together therewith longitudinally bounding said pocket, said connecting walls being of minimum thickness at their midportions, side portions on said connecting walls outwardly of said midportions and progressively thickening toward their connections with said first pair of walls, bearing surfaces on said side portions at corresponding sides of said midportions and inclined relative to and converging laterally toward one of said first-named friction surfaces, and faces on opposite sides of each of said shoes and each parallel to and engageable with one of said bearing surfaces.

2. In a draft gear having a housing, a friction pocket in and opening onto an end of said housing, a pair of counterpart friction shoes in said pocket and each having a friction face engageable with a friction surface on one of a pair of opposite longitudinal walls of said housing, and yieldable means acting between said shoes and urging said friction faces and surfaces into engagement, the combination of a pair of transversely spaced longitudinal walls connecting said first pair of walls and together therewith longitudinally bounding said pocket, said connecting walls being of minimum thickness at their midportions, side portions on said connecting walls outwardly of said midportions and progressively thickening toward their connections with said first pair of walls, bearing surfaces on said side portions at corresponding sides of said midportions and converging laterally toward a wall of said first pair and substantially coextensive longitudinally with said first-named friction surfaces, and a face on each side of each of said shoes and parallel to and normally spaced from one of said bearing surfaces and engageable therewith on shifting of said shoe toward said side.

3. In a draft gear having a housing, a friction pocket in and opening onto an end of said housing, a pair of counterpart friction shoes in said pocket and each having a friction face engageable with a friction surface on one of a pair of opposite longitudinal walls of said housing, and yieldable means acting between said shoes and urging said friction faces and surfaces into engagement, the combination of transversely spaced longitudinal walls connecting said first pair of walls and therewith longitudinally bounding said pocket, said connecting walls having substantially parallel outer faces and over their midportions being of substantially uniform thickness, inner surfaces on each of said connecting walls at opposite sides of the midportion thereof and coextensive longitudinally with said pocket, each of Said inner surfaces being substantially fiat and progressively diverging from the outer face of its wall toward an adjoining wall of said first pair, and a fiat face at each side of each shoe and inclined in correspondence with and confronting and normally spaced from one of said inner surfaces, said side faces being engageable with said inner surfaces on lateral shifting of said shoes.

(References on following page) References Cited in the le of this patent UNITED STATES PATENTS Symons Dec. 26, 1922 OConnor Mar. 9, 1926 Barrows Oct. 25, 1932 6 Barrows Dec. 3, 1935 Blattner Sept. 8, 1936 Clark et a1 Aug. 25, 1952 Cottrell Oct. 30, 1956 Andrews et a1 Sept. 29, 1959 

